Numerical simulations of the textbook neutrino-reheating
mechanism for core collapse supernovae frequently fail to
match the most fundamental observable property, an explosion
with roughly 1051 ergs of kinetic energy. This failure
raises the suspicion that the neutrino-reheating paradigm
might not be the whole story of the core collapse supernova
mechanism. One weakness in the current generation of models
is incomplete nuclear and neutrino physics. In particular,
electron capture on nuclei, the most important weak nuclear
interaction to the dynamics of stellar core collapse, has
been treated in a highly parameterized fashion, if not
ignored. With realistic treatment of electron capture on
heavy nuclei comes significant changes in the hydrodynamics
of core collapse and bounce. We discuss these as well as the
ramifications for the post-bounce evolution in core collapse
supernovae.